Imaging cAMP Dynamics in the Drosophila Brain with the Genetically Encoded Sensor Epac1-Camps

Cyclic adenosine monophosphate (cAMP) is a critical second messenger signaling molecule, the modulation of which is a central mode of nervous system function. The development of genetically encoded sensors for cAMP has made it possible to measure cAMP dynamics within living cells with high temporal and spatial resolution. In this chapter, we review live-imaging methods for the measurement of relative cAMP levels within single neurons of the explanted adult Drosophila brain. Specifically, we describe a detailed protocol for the monitoring of neuronal cAMP dynamics during bath application of neurotransmitters and neuromodulators using the genetically encoded cAMP sensor Epac1-camps and scanning laser confocal microscopy.